1. Field of the Invention
This invention relates to the microwave preparation of food. More particularly, it relates to the release of food aromas during the microwave preparation of food. This invention especially relates to compositions which will release aromas of cooking food during microwave preparation of comestibles.
2. Description of the Prior Art
Microwave ovens for home use have found widespread acceptance. The fact that the cooking and/or reheating of food in the domestic microwave oven is achieved in such relatively short periods of time is probably the principal reason for the high sales of these units in recent years.
Essentially all domestic microwave ovens operate at 2450 MHz. The dielectric properties of food at this frequency parallels those of water which is the principal lossy constituent of food. The absorption of microwave energy by food by the interaction of the dipole water molecule in the microwave field results in a localized heating resulting in the desired cooking or reheating. Despite the widespread use of microwave ovens, a major shortcoming involved in their use is the lack of desirable aroma release from comestibles during their preparation by microwave heating. The reason for this may be attributed to the basic functioning of the microwave oven. Since the action of microwave energy on the dipole water molecule is the principal cause of heat generation within the water-containing comestible, the maximum temperature obtainable on a comestible surface exposed to microwave energy is about 100.degree. C. In a thermal oven, normal cooking and roasting temperatures are in the range of about 175.degree. to about 235.degree. C. (350.degree.-450.degree. F.). Further, the short cooking times achieved by using a microwave oven may also contribute to the lack of aroma generation from the comestible. It is thought that the combination of temperatures in excess of 100.degree. C. and periods of time in excess of about 5 minutes are necessary for the typical generation and release of the familiar roasting or cooking aromas. Thus, the very features of the microwave oven which make it so attractive to people anxious to quickly prepare a tasty meal, prevent the generation of kitchen aromas which would be harbingers of the upcoming meal.
The generation or release of aromas from comestibles being prepared in a microwave oven would enhance the usefulness of this appliance, as well as, increasing the acceptance of microwaveable convenience foods provided with an appropriate aroma-releasing composition.
Recently in U.S. Pat. No. 4,857,340 to T. Parliment et al. entitled Aroma Release During Microwave Cooking a composition of an aroma-producing material was taught which comprises an aroma-producing material enrobed in a lipid in combination with a microwave susceptible material. Upon exposure to microwave radiation, the rapid heat generated by the microwave susceptible material would melt the lipid thereby releasing the aroma. The microwave susceptible material could be a solid such as a heater board or it could be a liquid such as glycerol or propylene glycol which could be admixed with the aroma and lipid. However the microwave susceptible liquids may not be appropriate to be topically applied to a food product because they may contribute an off-flavor to the food on which they are applied.
It is an object of this invention to provide aroma production during microwave preparation of comestibles.
It is another object of the invention to provide aroma-producing compositions for use when comestibles are prepared in a microwave oven, preferably a composition which may be topically applied to the comestible without contributing an off-flavor to the comestible after cooking or reheating.